The present invention relates to chemical compounds that inhibit MKNK1 kinase (also known as MAP Kinase interacting Kinase, Mnk1) and/or MKNK2 kinase (also known as MAP Kinase interacting Kinase, Mnk2). Human MKNKs comprise a group of four proteins encoded by two genes (Gene symbols: MKNK1 and MKNK2) by alternative splicing. The b-forms lack a MAP kinase-binding domain situated at the C-terminus. The catalytic domains of the MKNK1 and MKNK2 are very similar and contain a unique DFD (Asp-Phe-Asp) motif in subdomain VII, which usually is DFG (Asp-Phe-Gly) in other protein kinases and suggested to alter ATP binding [Jauch et al., Structure 13, 1559-1568, 2005 and Jauch et al., EMBO J25, 4020-4032, 2006].MKNK1a binds to and is activated by ERK and p38MAP Kinases, but not by JNK1.MKNK2a binds to and is activated only by ERK. MKNK1 b has low activity under all conditions and MKNK2b has a basal activity independent of ERK or p38MAP Kinase. [Buxade M et al., Frontiers in Bioscience 5359-5374,May 1, 2008]
MKNKs have been shown to phosphorylate eukaryotic initiation factor 4E (elF4E), heterogeneous nuclear RNA-binding protein A1 (hnRNP A1), polypyrimidine-tract binding protein-associated splicing factor (PSF), cytoplasmic phospholipase A2 (cPLA2) and Sprouty 2 (hSPRY2) [Buxade M et al., Frontiers in Bioscience 5359-5374,May 1, 2008]. elF4E is an oncogene that is amplified in many cancers and is phosphorylated exclusively by MKNKs proteins as shown by KO-mouse studies [Konicek et al., Cell Cycle 7:16, 2466-2471, 2008; Ueda et al., Mol Cell Biol 24, 6539-6549, 2004]. elF4E has a pivotal role in enabling the translation of cellular mRNAs. elF4E binds the 7-methylguanosine cap at the 5′ end of cellular mRNAs and delivers them to the ribosome as part of the elF4F complex, also containing elF4G and elF4A. Though all capped mRNAs require elF4E for translation, a pool of mRNAs is exceptionally dependent on elevated elF4E activity for translation. These so-called “weak mRNAs” are usually less efficiently translated due to their long and complex 5′UTR region and they encode proteins that play significant roles in all aspects of malignancy including VEGF, FGF-2, c-Myc, cyclin D1, survivin, BCL-2, MCL-1, MMP-9, heparanase, etc. Expression and function of elF4E is elevated in multiple human cancers and directly related to disease progression [Konicek et al., Cell Cycle 7:16, 2466-2471, 2008].
MKNK1 and MKNK2 are the only kinases known to phosphorylate elF4E at Ser209. Overall translation rates are not affected by elF4E phosphorylation, but it has been suggested that elF4E phosphorylation contributes to polysome formation (i.e. multiple ribosome on a single mRNA) that ultimately enables more efficient translation of “weak mRNAs” [Buxade M et al., Frontiers in Bioscience 5359-5374, May 1, 2008]. Alternatively, phosphorylation of elF4E by MKNK proteins might facilitate elF4E release from the 5′ cap so that the 48S complex can move along the “weak mRNA” in order to locate the start codon [Blagden S P and Willis A E, Nat Rev Clin Oncol. 8(5):280-91, 2011]. Accordingly, increased elF4E phosphorylation predicts poor prognosis in non-small cell lung cancer patients [Yoshizawa et al., Clin Cancer Res. 16(1):240-8, 2010]. Further data point to a functional role of MKNK1 in carcinogenesis, as overexpression of constitutively active MKNK1, but not of kinase-dead MKNK1, in mouse embryo fibroblasts accelerates tumor formation [Chrestensen C. A. et al., Genes Cells 12, 1133-1140, 2007]. Moreover, increased phosphorylation and activity of MKNK proteins correlate with overexpression of HER2 in breast cancer [Chrestensen, C. A. et al., J. Biol. Chem. 282, 4243-4252, 2007]. Constitutively active, but not kinase-dead, MKNK1 also accelerated tumor growth in a model using Ep-Myc transgenic hematopoietic stem cells to produce tumors in mice. Comparable results were achieved when an elF4E carrying a S209D mutation was analyzed. The S209D mutation mimicks a phosphorylation at the MKNK1 phosphorylation site. In contrast, a non-phosphorylatable form of elF4E attenuated tumor growth [Wendel H G, et al., Genes Dev. 21(24):3232-7, 2007]. A selective MKNK inhibitor that blocks elF4E phosphorylation induces apoptosis and suppresses proliferation and soft agar growth of cancer cells in vitro. This inhibitor also suppresses outgrowth of experimental B16 melanoma pulmonary metastases and growth of subcutaneous HCT116 colon carcinoma xenograft tumors without affecting body weight [Konicek et al., Cancer Res. 71(5):1849-57, 2011]. In summary, elF4E phosphorylation through MKNK protein activity can promote cellular proliferation and survival and is critical for malignant transformation. Inhibition of MKNK activity may provide a tractable cancer therapeutic approach. Furthermore it has been found that MKNK1 is an acinar cell-specific kinase required for exocrine pancreatic secretion [Cendrowski J, Sanchez-Arévalo Lobo V J, Sendler M, et al. Gut Published Online First: Jul. 18, 2014; doi:10.1136/gutjnl-2013-306068].
The kinases MKNK1 and MKNK2 are important downstream targets of the Erk and p38 mitogen-activated protein kinase (MAPK) pathways and their activity can also be modulated by MAPK independent signals. The MKNKs are directly involved in regulating mRNA translation and, therefore, are key mediators of oncogenic progression and cytokine signaling. In particular, MAPK pathways such as Erk and p38 have been shown to play important roles in modulating immune responses by mediating the production of cytokines that control the initiation of innate immunity; the activation of adaptive immunity; and by regulating cellular responses to cytokines involved in immune responses. In addition, Erk and p38 contribute to pain sensitivity and p38 kinase inhibitors have shown pre-clinical and clinical efficacy regarding pain [Brown, Heitmeyer, et al., J Inflamm (Lond), 2008; Hill, Dabbagh, et al., J Pharmacol Exp TherJi, 2008; Gereau, et al., Brain Res Rev, 2009; Cheng, Dauch, et al., Mol Pain, 2010; Anand, Shenoy, et al., European Journal of Pain, 2011; Daves, Aitchison, et al., American College of Rheumatology Annual Meeting, 2012; Lin, Wang, et al., Curr Med Chem, 2014]. As MKNK kinases are effectors of MAPK pathways, these observations suggest that they may play important roles in mediating cytokine production and inflammatory pain. Recent studies support the involvement of MKNK kinases in different inflammatory processes [Rowlett, Chrestensen, et al., Am J Physiol Gastrointest Liver Physiol, 2008; Kjellerup, Kragballe, et al., Experimental Dermatology, 2008; Melemedjian, Asiedu, et al., J Neurosci, 2010; Fortin, Mayer, et al., Journal of Leukocyte Biolog, 2013]. Due to the induction of MKNK kinases by different inflammatory stimuli (sterile inflammation and pathogens) and their ability to regulate the expression of different cytokines which mediate the pathogenesis of multiple disorders such as auto-immune diseases, allergies, neurological disorders, sepsis, cardiovascular diseases, metabolic diseases, obesity and cancer. MKNKs represent a central node in regulating inflammation. [Joshi et al.; World J Biol Chem 2014 Aug. 26; 5(3): 321-333; Joschi et al., Biomol Concepts. 2012 April; 3(2): 127-139]
Imbalance in cytokines from Interleukin-1 family and their role in the pathogenesis of Endometriosis has been reported in the literature [American Journal of Reproductive Immunology 68 (2012) 138-145] as well as the possible pathophysiological roles of Mitogen-Activated Protein Kinases (MAPKs) in Endometriosis [Yoshino et al.; AJRI 2004; 52: 306-311]. More recently, the role of pro-inflammatory cytokines for evaluation of inflammatory status and their pathogenetic mechanisms in endometriosis has been illustrated [Tosti et al.; Reproductive Sciences 2015, 1-7; Malutan et al., Centr Eur J Immunol 2015; 40 (1): 96-102; Soo Hyun Ahn et al., BioMed Research International, Vol. 2015, Article ID 795976, 12 pages]. Women with endometriosis have elevated levels of key pro-inflammatory cytokines, i.e. IL-1β, IL-6, and TNF-α. At the same time, IL-1β and IL-6 could be used as predictors for endometriosis.
Substituted pyrazolopyridinamine compounds of general formula (I) have not been disclosed in prior art for the treatment or prophylaxis of different diseases.
So, the state of the art described above does not describe the specific substituted pyrazolopyridinamine compounds of general formula (I) of the present invention as defined herein or a stereoisomer, a tautomer, an N-oxide, a hydrate, a solvate, or a salt thereof, or a mixture of same, as described and defined herein, and as hereinafter referred to as “compounds of the present invention”, or their pharmacological activity.
It has now been found, and this constitutes the basis of the present invention, that said compounds of the present invention have surprising and advantageous properties.
In particular, said compounds of the present invention have been found to effectively inhibit MKNK1 kinase.
Furthermore, the compounds according to the present invention have been found to effectively inhibit MKNK2 kinase.
In contrast to other MKNK1 and/or MKNK2 kinase inhibitors, the pyrazolopyridinamines according to the invention are mainly active on sterile and pathogenic inflammatory responses and do not interfere directly with cell viability.
The pyrazolopyridinamines according to the present invention may be used for the treatment or prophylaxis of diseases of uncontrolled cell growth, proliferation and/or survival, inappropriate cellular immune responses, or inappropriate cellular inflammatory responses or diseases which are accompanied with uncontrolled cell growth, proliferation and/or survival, inappropriate cellular immune responses, or inappropriate cellular inflammatory responses, particularly in which the uncontrolled cell growth, proliferation and/or survival, inappropriate cellular immune responses, or inappropriate cellular inflammatory responses is mediated by MKNK1 and/or MKNK2 kinase, such as, for example, haematological tumours, solid tumours, and/or metastases thereof, e.g. leukaemias and myelodysplastic syndrome, malignant lymphomas, head and neck tumours including brain tumours and brain metastases, tumours of the thorax including non-small cell and small cell lung tumours, gastrointestinal tumours, endocrine tumours, mammary and other gynaecological tumours, urological tumours including renal, bladder and prostate tumours, skin tumours, and sarcomas, and/or metastases thereof.
The pyrazolopyridinamines according to the present invention may be used for the treatment or prophylaxis of inflammatory and/or immunological diseases as described in the summary of the invention.
Furthermore, the compounds according to the invention may be used for the treatment or prophylaxis of a gynecological disease, preferably dysmenorrhea, dyspareunia or endometriosis, adenomyosis, endometriosis-associated pain, or other endometriosis-associated symptoms, wherein said symptoms are in particular endometriosis-associated proliferation, dysmenorrhea, dyspareunia, dysuria, or dyschezia.